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jimfulco · 12-24-2004, 01:24 AM

Go to http://novaresource.org/speedo.htm & you can use your axle ratio & tire diameter to calculate the speedo gear ratio you need. If you get lucky, you can use the drive gear that's already on your trans output shaft & only change the driven gear, which should be available at the nearest Chevy place. If not, you can get a drive gear at http://www.dandltransmission.com/muncie.html (you'll need to know if the drive gear is metal or plastic, as the metal ones are pressed on & the plastic ones use a retaining clip).

Just because it might be easier, count the teeth on your driven gear (the one the speedo cable hooks to) & multiply by 3.07 & divide by 3.73. If it comes out a whole number (or close) between 18 & 23, just get a driven gear with that many teeth.

12-24-2004, 01:24 AM	#2
jimfulco Registered User Join Date: May 2003 Location: Shreveport LA Posts: 3,170	Go to http://novaresource.org/speedo.htm & you can use your axle ratio & tire diameter to calculate the speedo gear ratio you need. If you get lucky, you can use the drive gear that's already on your trans output shaft & only change the driven gear, which should be available at the nearest Chevy place. If not, you can get a drive gear at http://www.dandltransmission.com/muncie.html (you'll need to know if the drive gear is metal or plastic, as the metal ones are pressed on & the plastic ones use a retaining clip). Just because it might be easier, count the teeth on your driven gear (the one the speedo cable hooks to) & multiply by 3.07 & divide by 3.73. If it comes out a whole number (or close) between 18 & 23, just get a driven gear with that many teeth. Last edited by jimfulco; 12-24-2004 at 01:27 AM.